Malicious PDF — malware analysis report

Static analysis result for SHA-256 4590a22309271e8a…

MALICIOUS

PDF

119.5 KB Created: 2021-07-18 19:42:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3f764167a8806ae7e2b5e7b9ba013b2a SHA-1: 664748cbecd0dca6d14dccc860a78aeb75f5e1ae SHA-256: 4590a22309271e8aa98bbe99999214cc23b4ff8e1ce52ba9772ae4ed51d44573
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised CMS upload directories. The primary purpose appears to be directing users to potentially malicious content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/1925b1c6f2176e61d7b03e228840742c/32752043148.pdf In PDF document text
    • http://clear-es.net/yamituki-n/uploads/files/kinukewazom.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ba62be1ab5e---65223201902.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070ac7e05a82---figefumujifisike.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/2ccd02caaa1997eefaad927e11216322/mepekaluripusut.pdfIn PDF document text
    • https://rittenhousesmiles.com/wp-content/plugins/super-forms/uploads/php/files/7548af6fa27de4000825141853dd7338/50890618814.pdfIn PDF document text
    • http://oldtimerclub-thueringerberg.at/images/file/ferebizedusamifalo.pdfIn PDF document text
    • http://elite-nails.pl/Upload/file/vijizugubab.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/6dfbb3f4699125b30dfe48eb9b0c5111/64927646829.pdfIn PDF document text
    • http://nhadephoanhao.vn/upload/ckupload/files/xokigas.pdfIn PDF document text
    • http://jyjwqj.com/uploadfile/file///2021051800005852.pdfIn PDF document text
    • http://graylegalservices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fagedu.pdfIn PDF document text
    • https://psychologgia.pl/Upload/file/pijepibukenubixawe.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16079880e18406---tusinejux.pdfIn PDF document text
    • http://shethof.ch/cgi-bin/dynamisch/file/95756935376.pdfIn PDF document text
    • https://serviceservice.eu/userfiles/file/mofebuxerigabuf.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/clt2mkvpa8tvd7vgmh1hmb7e16/wejuwofo.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/t3tdjb25lg8f1321rj9g48k957/napifowi.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a3495bad3c5---visifexagerujugibofew.pdfIn PDF document text
    • http://attep.com/home/sandbox/domains/heekee.com.hk/public_html/ckfinder/userfiles/files/72302124557.pdfIn PDF document text
    • http://gwardiajuvenia.pl/zdjecia/fck/file/81473567009.pdfIn PDF document text
    • http://webinaris.net/ckfinder/userfiles/publics/files/25983949835.pdfIn PDF document text
    • https://rsun.pro/admin/ckfinder/userfiles/files/34017666094.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=how+to+annotate+an+article+examplePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000173ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x173AC 17344 bytes
SHA-256: d6eb49ceac381ac8e2f258508c1fde092d005dfecae8d7cc75e55c597764ac17
font_01_sfnt_off0001a072.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A072 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001b889.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B889 10548 bytes
SHA-256: e0a7bee10eea5be0a59f83935c93f6f29d6264a49d222bce01b74b7a7733cebe